How to scale snapped measure along with objects?
You cannot scale measure bars, but you can get what you want with some arithmetic. In the bottom right, the 3D View editor has a dark grey box that appears when you do something like scale. This is the Adjust Last Operation Panel (blender docs link). Click the little arrow on it's left to open it up, and you'll see adjustment wigets for whatever you just did. In the case of scale, you'll mainly see 3 numbers that correspond to the 3 axes. IE: 2, 2, 2 means the object is twice as long on each axes (or 2^3= 8 times bigger volume-wise). It's basic multiplication from there: Current measurement*[SOLVE FOR FACTOR]=desired measurement. Enter that factor in all three areas, and you're good to go.